* while salaries are higher than eg most of Europe, they're still nowhere near the US - US salaries are often at least double (or more, a lot more)
* their cost of living and taxes are high
* they're backwards and insular (maybe you think the US is too, but the US has 350 million people, Australia has like 25, lol, so insular takes on a whole new meaning there)
* they're not as diverse as the US (sure, London is diverse, but still, the diversity of the US smokes them all, so many different cities here with so many different demographics, climates etc etc)
I'm saying that as a Scandi who's lived in UK, Canada, Australia and now US. Of course the US has a lot of problems too, but as a destination for skilled immigrants, the others don't even compare IMO.